New Radeon 7990 fluctuating hash rate..

[c33fax]

Hi, so just fitted a brand new 7990 Radeon gpu... But when I use GUIMiner it seems every second the hash value is changin from 70 Mhash to 169 then 490  then to 'connecting...'  this then repeats but with different values...

Also when I log into BTC Guild my average speed is about 490Mhah, half what this card can do.... 

Any ideas

[Bitcoin Merchant]

Sorry I dont understand

[c33fax]

Sorry I dont understand

What don't you understand?    1 x Radeon Card 7990 has a fluctuating Mhash - is this normal?   I'd thought each gpu core of the 7990 would  mine at around 500 Mhash .     but there up and down like a tart's knickers.. also getting the 'connecting' alot on the GUIMiner.. maybe I should try a different software miner ??  ?

[Bitcoin Merchant]

yea its normal dont be worried

[Xanthe]

Sorry I dont understand

What don't you understand?    1 x Radeon Card 7990 has a fluctuating Mhash - is this normal?   I'd thought each gpu core of the 7990 would  mine at around 500 Mhash .     but there up and down like a tart's knickers.. also getting the 'connecting' alot on the GUIMiner.. maybe I should try a different software miner ??  ?

The "connecting..." part makes it seem like there may be some connection issues. I'd definitely try another pool briefly just for testing purposes to rule that out. I don't have any experience with GUIMiner but if you decide to try another piece of software I'd certainly recommend CGMiner. One common cause of fluctuations in hash rate is the card's "power limit" setting. If it's set too low for the workload, the card will throttle back resulting in a loss of hash rate. If this is the case you should be able to see the card's clock speeds bouncing around in monitoring software. You can raise the power limit in the Catalyst Control Center under the performance tab (or in another piece of tweaking software).

I can't really offer much help beyond this as I have zero experience with 7990s, sorry.

Good luck.

[ranlo]

Hi, so just fitted a brand new 7990 Radeon gpu... But when I use GUIMiner it seems every second the hash value is changin from 70 Mhash to 169 then 490  then to 'connecting...'  this then repeats but with different values...

Also when I log into BTC Guild my average speed is about 490Mhah, half what this card can do.... 

Any ideas

There are a couple things: one could be bad settings on the card itself. Are you overclocking or using stock? Another is that it could be a faulty card.

Also, if you restart the PC does it have the same issue?

[horosho]

I am having similar problems with XFX 7990 using GUIMiner. The hash rate fluactuates and then after 4-5 minutes I get a "Connections Problem" message and then the hash rate drops from 500MH/s to 100KH/s.  Anyone know how to fix this? pls advise...thanks

[carly200]

anybody got some hash and watt at the wall readings from the 7990

[Gator-hex]

Try installing the latest AMD Catalyst drivers. It sounds like only 1 core is active. You should be able to get 1Gh/s+

I used to run GUIminer twice and select a different core on each one. (imagine it as 2 graphic cards, not 1)

Not having a PCI-3.0 slot can also effect it's performance too, but I would have think gaming only, not mining.